Water filtration has become common in homes, offices and other places to produce cleaner and better tasting water. Accordingly, water containers such as pitchers have been equipped with filtration systems. In some instances, these filtration systems may employ a filter core through which water passes as a reservoir of the water container is filled. The filtered water than can be dispensed from the reservoir. This design approach has proven problematic however and attention has accordingly shifted to other designs, such as filter-as-you-pour (FAYP) configurations.
In general, FAYP devices are configured with a reservoir that holds a volume of unfiltered fluid. The fluid passes through the filter as it is dispensed from the reservoir. This configuration is an improvement on earlier designs in some respects, but at least some FAYP devices nonetheless present some problems.
For example, some FAYP devices are configured in such a way that a significant amount of fluid in the reservoir can bypass the filter as the fluid is dispensed from the reservoir. This can occur because the fluid pathway between the filter and the outlet of the reservoir is not closed, or at least is not substantially closed. This fluid pathway configuration can arise due to the placement of the filter in the reservoir. In particular, the filter may be located in a location in the reservoir that is spaced well away from the outlet, such as about midway between opposing walls of the reservoir. Because the fluid pathway between the filter and the outlet is not closed, fluid from the reservoir can readily bypass the filter and exit the reservoir.
This problem can be appreciated by considering a substantially full fluid container disposed in a nearly horizontal dispensing position, where the filter is located approximately midway between opposing walls of the reservoir, and where the outlet of the reservoir is located on or near the lowermost wall of the reservoir. Thus, the walls of the reservoir and the filter are all generally horizontal in their orientation. In this circumstance, about half or more of the fluid in the reservoir resides in the space between the filter and the outlet and thus can readily pass through the outlet without first passing through the filter. Moreover, while fluid located in the space between the uppermost wall of the reservoir and the filter may possibly pass through the filter prior to exiting through the outlet, the open path between the filter and the outlet allows the possibility that filtered water can mix with unfiltered water prior to being dispensed from the reservoir.
This problem may become more acute in circumstances where the reservoir is less than full. For example, and depending upon the fullness of the reservoir, it may be the case that when the reservoir is tipped to a nearly horizontal, or other, dispensing position, all or nearly all of the fluid in the reservoir resides in the space between the filter and the outlet and thus can readily pass through the outlet without first passing through the filter. In this circumstance, little or no filtration occurs as fluid is dispensed from the reservoir. As with the other problems noted above, such result leads to a poor experience for the consumer.
A related problem concerns the fluid resistance offered by the filter. The filter, by its nature, tends to provide some resistance to flow through the filter. Thus, from this perspective at least, the filter can be considered to act as a flow restrictor. However, the fluid in the reservoir will tend to follow the path of least resistance when exiting the reservoir and as such, that fluid will tend to pass around the filter rather than through the filter.
Finally, the location of the filter and the fluid resistance offered by the filter have at least one other unfavorable implication. In particular, and with reference again to the example circumstance where a substantially full fluid container is in a generally horizontal position, the filter may be located about mid-depth in the fluid. Because the hydrostatic pressure of the fluid varies from a maximum at the bottom of the fluid to a minimum at the surface of the fluid, the hydrostatic pressure of the fluid just above the filter is significantly less than the maximum hydrostatic pressure. As a result, the flow rate through the filter, which is a function of the hydrostatic pressure of the fluid above the filter, is significantly compromised.
In light of problems such as those noted above, it would be useful to provide a fluid container configured to define a closed, or substantially closed, fluid pathway between a filter and a reservoir outlet. Further, it would be useful to provide a fluid container configured to implement any one or more of reduction or minimization of the amount of unfiltered water left in the fluid container after a dispensing event, reduction or substantial elimination of bypass around the filter, and achievement of relatively higher flow rates based on hydrostatic pressure at the filter. As well, it would be useful to provide a fluid container configured such that the filter is located relatively close to the outlet of the container. Finally, it would be useful to provide a fluid container configured to enable placement of a filter relatively close to the side of the fluid container where the outlet is located. Any of the aforementioned containers could take the form of a filter-as-you-pour container.